The present invention relates to a method and a device for insulating adjacent to a roof or other flat building structure while maintaining a ventilation gap between the insulation material and the flat building structure to allow for air to flow. This ventilation gap, in conjunction with vents, such as ridge vents, improves airflow as well as insulation efficiency (thermal and sound).
It is known to mount rigid insulation sheets below a roof while maintaining a ventilation gap by using brackets, as disclosed in U.S. Pat. No. 7,017,315 “Corwin”. Corwin says in column 4, lines 22-28 that for any of the roof structures shown in FIGS. 1-4 the brackets could be mounted on the rafters first and then the insulating panels 16 installed later, or the brackets could first be secured to the insulating panels and then secured to the rafters. However, it does not appear that all those structures really could be installed in either order as stated.
It appears that the embodiments shown in FIGS. 3-10 would require assembling the panel 16 onto the brackets before installing the brackets onto the rafters, because there would be no way to assemble the insulating panel 16 onto those brackets after the brackets are installed.
The embodiments of FIGS. 1 and 2, which do not have an upper stop above the insulating panel to prevent the insulating panel from moving into the ventilation gap, would permit the brackets to be installed first, before assembling the panel 16 onto the brackets, because, in those embodiments, the insulating panel 16 could be dropped in from the open top before installing the roof. However, since there is no upper stop in those embodiments, if the insulating panel is not later secured to the brackets, only the force of gravity is holding the rigid panel 16 in place to maintain the ventilation gap.
Thus, the various embodiments of Corwin do not provide the convenience of being able to install the brackets onto the rafters first and then installing the rigid panels onto the brackets while also providing a positive upper stop between the insulating panel and the roof or other flat building structure in order to ensure that the desired ventilation gap is maintained.